Hi, you need to remove the plastic part which is visible in the picture I posted (arrow 2 is pointing at it) you can remove it by taking out the 3 or 4 plastic plugs which you can see from the inside. After removing those you can just pull the plastic part off.I have the same problem with leaking. I found out that there is water in toolkit area 2 weeks ago and let drained it through the plug.
I took out lower mats and toolkit from the trunk and left it like that so i can follow how it acts since there is a lot of rain here in Croatia lately. So the water is definitely coming through boot doors. Past weekend i did not drive the car and left it in the parking on the rain, and it filled with decent amount of water (you can see in the attached picture)
View attachment 68035
So my question for Franck, did you remove all the plastics and side panels like Migomes did, or you just removed the rubber seal and cleaned it and returned it back? If you had to remove the plastics, do you maybe have car manual which shows the right way to remove it or you did it just by trying? I just do not want to break any of the plastics or side panels if i have to remove them!
And also the most important question, does it works and keeps boot dry or it leaked again?
And yes! Cleaning behind the seal solved my problem. The boot has stayed dry.